Refrigeration apparatus



Nov. 28, 1939. a. s. M cLoY REFRIGERATION APPARATUS 2 Shets-Sheet 1 Filed Jan. 29, 1938 s an. 2.

INVENTOR GRAHAM. S. MCL.oY.,

ATTOREY WITNESSES:

Nov. 28, 1939. s. s. M CLOY REFRIGERATION APPARATUS 2 Sheets-Sheet 2 Filed Jan. 29, 1938 Pas-.5.

FGGG

WITNESSES:

INVENTOR Y O L C C- s M A H A R G ATTORNZU Patented Nov. 28, 1939 REFRIGERATION APPARATUS Graham S. McCloy, East Longmeadow, Mass, assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pemisylvania Application January 29, 1938, Serial No. 187,591

18 Claims.

This application is a continuation in part of my application, Serial No. 122,905, filed January 29, 1937 for Refrigeration apparatus.

It is an object of my invention to provide reirigeration apparatus in which the efficiency is improved by the use of novel heat exchange devices in the system.

It is another object of my invention to provide a novel arrangement of parts for controlling the flow of refrigerant between the high and the low pressure sides of a refrigerating system.

It is a further object of my invention to provide an improved heat exchanger between the suction conduit and capillary tube of a refrigerating system, in which the conduit and tube are metallically connected together for a considerable portion of their respective lengths.

It is still another object of my invention to provide a novel heat exchanger for a refrigerating system and to improve the operation of the heat exchanger by surrounding it with heat insulation, preferably heat insulation associated with the refrigerator cabinet.

It is still a further object of my invention to provide a heat exchanger embedded in the cabinet heat insulation which is readily applied to and removed from the refrigerator cabinet with other portions of the refrigerating system.

It is another object of my invention to provide a novel heat exchanger between the capillary tube and suction conduit of a refrigerating system which is associated with a heat insulated cabinet wherein part of the heat exchanger is disposed exteriorly of the cabinet and another part of the heat exchanger is disposed in the heat insulation. It is yet another object of my invention to provide an extremely compact heat exchanger bythe novel arrangement of the capillary tube with respect to the suction conduit.

These and other objects are effected by my invention as will be apparent from the following description and claims, taken in connection with the accompanying drawings, forming a part of this application, in which:

Fig. 1 is a diagrammatic view of a refrigeratin system embodying my invention;

Fig. 2 is a vertical sectional view of a portion of a refrigerator cabinet illustrating the application of my improved refrigerating system to a refrigerator cabinet;

Fig. 3 is an elevational view of the back of the refrigerator cabinet and illustrates the heat exchanger disposed exteriorly thereof; and,

Fig. 4 is an enlarged cross-sectional View, taken (Cl. 62--1ll5) on line IV-IV of Fig. 3 of the heat exchanger which is disposed exteriorly of the cabinet.

Referring specifically to the drawings for a detailed description of my invention, numeral ll designates a compressor for compressing refrigerant vapor and numeral 82 designates a motor for driving the compressor. Compressed refrigerant vapor is conveyed through a discharge conduit it to a condenser It, wherein it is cooled by a fan l5 and thus liquefied. Condensed refrigerant is then conveyed to portions 25] and it of a tube of considerable length and relatively small diameter, sometimes referred to as a capillary tube. After passing through the portions 2t] and 2E of the capillary tube, the refrigerant enters a portion 22 of the capillary tube, which is preferably helically coiled as shown in Figs. 1 and 2 for a substantial portion of its length.

Refrigerant then enters an evaporator or expansion vessel 25;, herein shown as a sheet metal, flooded type, wherein the refrigerant expands and absorbs heat. vaporized refrigerant is withdrawn from the evaporator 2:5 by the compressor it through a conduit 25. The gas passing through the conduit 25 is relatively cool, and is, therefore disposed in heat exchange relation as shown diagrammatically in Fig. 1, with the portions 2% and 2! of the capillary tube, which contains relatively ,warm liquid refrigerant from the condenser i i.

The compressor driving motor 52 is stopped and started by means of a temperature controlled switch 26 which has the contacts 229 closed and opened in response to the temperature of the evaporator through the expansion and contraction of the fluid in a bulb 2i and bellows 28. When the contacts 28 are bridged, the motor is energized from the line L1 and L2 and when the bellows 28 contracts due to a lower temperature of the evaporator 2d, the contacts 2% are opened, deenergizing the motor.

Referring now specifically to Figs. 2 and 3 of the drawings, a refrigerator cabinet 3i, having heat insulation 30, is shown. An aperture 32 is provided in'one of the heat insulated walls of the cabinet 3i for the reception of the evaporator 26, which is disposed normally in a food storage compartment 34 formed in the cabinet 3!. The evaporator 24 is preferably supported from a closure 35 for the aperture 32 by bracket 3t. The closure 35 is filled with heat insulation 3?. As shown in Fig. 3, the refrigerating mechanism comprising the motor, compressor and preferably the condenser are disposed in a machinery compartment 40 positioned below the food storage compartment 34. I

iii)

by vaporization in the evaporator.

As best shown in Figs. 2 and 3, the suction conduit-25 and the portion of the capillary tube extend from the machinery compartment 40 up the back of the cabinet exteriorly thereof, to the point where they enter the heat insulated closure 35. The suction conduit and portion 20 of the capillary tube are disposed in metallic heat exchange relation, preferably by soldering the two together, for substantially their entire extent after leaving the machinery compart-' ment 40 until they enter heat insulated closure 35. The suction conduit 25 is thus bonded to the capillary tube. This arrangement provides a portion of my heat exchanger and may be utilized without any further heat exchanger with resulting increase in efiiciency of the refrigeration system, because the liquid in the capillary tube is not only cooled, but is prevented from expanding, with resulting loss of useful refrigeration. Furthermore, the suction tube, particularly, has a tendency to condense moisture thereon, which may drip on the floor, and by disposing the capillary tube containing warm liquid refrigerant in heat exchange relation with the portion of the suction conduit which extends exteriorly of the cabinet, sweating and dripping are substantially eliminated.

A second heat exchanger is also provided, which may be used separately from or in conjunction with the heat exchanger just described. As shown in Figs. 2 and 3, the second heat exchanger is formed by coiling a portion 38 of the suction conduit 35 and imbedding it in the heat insulation 31 of the closure 35. The portion 2| of the capillary tube is helically wound about the portion 38 of the suction conduit 25 and is preferably soldered thereto. The coiled portion 22 of the capillary tube is also embedded in the heat insulation 31.

By retarding the expansion of refrigerant until it reaches the evaporator 24, and by cooling the liquid refrigerant in the portion 2| of the capillary tube, the efiiciency of the system is increased because a greater portion of the refrigerant compressed and condensed performs useful cooling In addition, the liquid refrigerant is cooled so that sensible heat need not be abstracted therefrom by vaporization of liquid in the evaporator 24, thus increasing the efficiency of the evaporator. Since the heat exchanger 20 and the helical coil 22 of the capillary tube are embedded in the insulation 31, the liquid in the capillary tube is not heated by contact with the relatively warm ambient air and expansion of the liquid is also retarded in this manner.

When the two heat exchangers are used in conjunction, as shown in the drawings, a very efficient heat exchanger is obtained since the coolest vaporized refrigerant is in heat exchange relation with the coolest liquid refrigerant and the warmest with the warmest. A substantial temperature differential is, therefore, maintained between the gas and the liquid at all points where the capillary tube and suction conduit are in heat exchange relation. Furthermore, a very important reason for the increase in efficiency of the heat exchangers, whether used separately or conjointly, is because of the large length of capillary tube and suction conduit which are metallically connected together. Any slight increase in work which must be done by the compressor due to superheating of the suction gas is more than offset by the gain effected.

From the foregoing it will be apparent that I have provided an improved refrigerating system from the standpoint of efflciency and have devised a novel flow control device between the high and low sides of the system, which device materially increases the efliciency of the machine.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

What I claim is:

1. In refrigerating apparatus. the combination of a compressor, a condenser, an evaporator, a refrigerator cabinet embodying a cooling compartment having an aperture therein for reception of the evaporator, a heat insulating closure for the aperture, a tube of small diameter and considerable length for restricting the flow of refrigerant from the condenser to the evaporator, and a suction conduit connecting the evaporator and the compressor, said tube and said suction conduit being disposed in heat exchange relation for a substantial portion of their lengths, said heat exchange portions being embedded in said heat insulated closure.

2. In refrigerating apparatus, the combination of' a compressor, a condenser, an evaporator, a refrigerator cabinet embodying a cooling compartment in which said evaporator is disposed, heat insulation surrounding said cooling compartment, a tube of small diameter and considerable length for. restricting the flow of refrigerant from the condenser to the evaporator, and a suction conduit for conveying vaporized refrigerant from the evaporator, said tube and said suction conduit being disposed in heat exchange relation for substantial portions of their lengths, said portions being surrounded by heat insulation, and another portion of said tube between the heat exchanger and they evaporator and embedded in said last-named heat insulation.

3. In refrigeration apparatus, the combination of a cabinet embodying a storage compartment and a machinery compartment, an evaporator associated with the storage compartment for abstracting heat therefrom, a refrigerating mechanism disposed in the machinery compartment, a capillary tube for conveying liquefied refrigerant from said mechanism to said evaporator and a suction conduit for conveying vaporized refrigerant from said evaporator to said mechanism, both said suction conduit and said capillary tube extending for a considerable distance outside said cabinet and being bonded in intimate metallic heat exchange'relation with each other for a substantial portion of said distance.

4. In refrigeration apparatus, the combination of a cabinet embodying a storage compartment,

of a cabinet embodying a storage compartment and a machinery compartment disposed therebelow, an evaporator for abstracting heat from the storage compartment disposed adjacent the top of the storage compartment, a refrigerating mechanism disposed in the machinery compartment, said mechanism including a condenser in which refrigerant is condensed, a capillary tube and a suction conduit for conveying liquid and gaseous refrigerant, respectively, between the evaporator and the mechanism, said cabinet having an opening therein adjacent the evaporator through which said tube and conduit extend, said capillary tube and suction conduit being metallically bonded together in intimate heat exchange relationship from approximately the point where they leave the machinery compartment near the bottom of the cabinet to the point where they enter the cabinet adjacent the evaporator.

6. In refrigeration apparatus, the combination of a cabinet embodying a storage compartment and a machinery compartment disposed therebelow, an evaporator for abstracting heat from the storage compartment disposed adjacent the top of the storage compartment, a refrigerating mechanism disposed in the machinery compartment, said mechanism including a condenser in which refrigerant is condensed, a capillary tube and a suction conduit for conveying liquid and gaseous refrigerant, respectively, between the evaporator and the mechanism, said cabinet having an opening in its back adjacent the evaporator through which said tube and conduit extend, said capillary tube and suction conduit being metallically bonded together in intimate heat exchange relationship exteriorly of the back of the cabinet from the point where they leave the machinery compartment near the bottom of the cabinet to the point where they enter the cabinet.

7. In refrigeration apparatus, the combination of a cabinet embodying a storage compartment and a machinery compartment, an evaporator associated with the storage compartment for abstracting heat therefrom, a refrigerating mechanism disposed in the machinery compartment, a capillary tube for conveying liquefied refrigerant from said mechanism to said evapo-= rator and a suction conduit for conveying vaporized refrigerant from said evaporator to said mechanism, both said suction conduit and said capillary tube extending for a considerable distance outside said cabinet and being bonded in intimate metallic heat exchange relation with each other for a substantial portion of said distance.

8. In refrigeration apparatus, the combination of a heat insulated cabinet embodying a storage compartment, an evaporator disposed in the storage compartment for abstracting heat therefrom, a refrigerating mechanism associated with the cabinet, a capillary tube for conveying liquefied refrigerant from said mechanism to said evaporator and a suction conduit for conveying vaporized refrigerant from said evaporator to said mechanism, said suction conduit and capillary tube being metallically connected to each other for a considerable portion of their respective lengths, and a portion of said conduit and said capillary tube being embedded in the heat insulation of the cabinet adjacent the outlet end of the capillary tube, said latter portions being in heat exchange relation with each other.

9. In refrigeration apparatus, the combination of a cabinet embodying a storage compartment surrounded by heat insulation and a machinery compartment disposed therebelow, an evaporator for abstracting heat from the storage compartment disposed adjacent the top of the storage compartment, a refrigerating mechanism disposed in the machinery compartment, said mechanism including a condenser in which refrigerant is condensed, a capillary tube and a suction conduit for conveying liquid and gaseous refrigerant, respectively, between the evaporator and the mechanism, said cabinet having an opening therein adjacent the evaporator through which said tube and conduit extend, said capillary tube and suction conduit being metallically connected together from substantially the point where they leave the machinery compart= ment near the bottom of the cabinet to the point where they enter the cabinet, and a portion of said suction conduit and said capillary tube being embedded in the heat insulation of the cabinet adjacent the outlet end of the capillary tube, said latter portions being in heat exchange relation with each other.

10. In refrigeration apparatus, the combination of a cabinet embodying a storage compartment and a machinery compartment disposed therebelow, an evaporator for abstracting heat from the storage compartment disposed adjacent the top of the storage compartment, a refrigerating-mechanism disposed in the machinery compartment, said mechanism including a condenser in which refrigerant is condensed, and a capillary tube and a suction conduit for conveying liquid and gaseous refrigerant, respectively, between the evaporator and the mechanism, said cabinet having an opening in its back adjacent the evaporator through which said tube and conduit extend, said capillary tube and suction conduit being metallically connected together exteriorly of the back of the cabinet from the point where they leave the machinery compart= ment near the bottom of the cabinet to the point where they enter the cabinet, and a portion of said suction conduit and said capillary tube being embedded in the heat insulation of the cabinet adjacent the outlet end of the capillary tube, said latter portions being in heat exchange relation with each other.

11. In refrigeration apparatus, the combination of a heat insulated cabinet embodying a storage compartment and a machinery compartment, an evaporator disposed in the storage compartment for abstracting heat therefrom, said storage cornpartment having an opening therein through which said evaporator is insertable, a heat insulated plug for closing said opening, a refrigerating mechanism disposed in the machinery compart ment, a capillary tube for conveying liquefied refrigerant from said mechanism to said evapo rator and a suction conduit for conveying vaporized refrigerant from said evaporator to said mechanism, both said suction conduit and said capillary tube extending for a considerable distance outside said cabinet and being in metallic heat exchange relation with each other for a substantial portion of said distance, and a portion of said suction conduit and said capillary tube being embedded in said heat insulated plug, said latter portions of the capillary tube and the suction conduit also being in heat exchange relation with each other.

12. In a refrigerating system, an expansion vessel, a tube for conducting the refrigerant liquid to the expansion vessel, said tube being of Bit small diameter to restrict the flow of the re- 7 frigerant liquid therethrough, and. a conduit of substantially larger diameter than said tube for conducting the refrigerant vapor from said expansion vessel, substantial portions of the walls of said tube and conduit being bonded together by a high heat transmitting material into intimate heat exchange relationship with one another and exposed to the ambient atmosphere. if

13. In a refrigerating system, in combination, a compressor, a condenser, an evaporator, a tube of small diameter and considerable length for 4 restricting the flow of refrigerant liquid from the condenser to the evaporator, and a suction conduit of substantially larger diameter than said tube for conveying vaporized refrigerant from the evaporator, substantial portions of the walls of said tube and said suction conduit being disposed in intimate metallic heat conducting relationship and exposed to the ambient atmosphere.

14. In refrigerating apparatus, the combination of a heat insulated cabinet, an evaporator for abstracting heat from said cabinet, refrigerant-supplying apparatus outside of said cabinet, a capillary flow-restricting tube for conducting the relatively warm liquid refrigerant from said refrigerant supplying apparatus to said evaporator and providing a pressure differential therebetween, and a suction tube for conducting the relatively cold vaporized refrigerant from the evaporator to the refrigerant-supplying apparatus, said capillary and suction tubes being in intimate heat conducting relationship with one another in the ambient atmosphere adjacent said cabinet, whereby the temperature of the suction tube in the ambient atmosphere is raised above the dew-point temperature thereof by the relatively warm liquid refrigerant in the capillary tube regardless of the temperature of the vaporized refrigerant in the suction tube.

15. In refrigeration apparatus, the combination of a heat insulated cabinet, an evaporator for abstracting heat from said cabinet, refrigerant compressing and cooling apparatus outside of said cabinet, a capillary flow-restricting tube providing substantially the sole flow-impeding device for the relatively warm liquid refrigerant flowing from said refrigerant-coolingv apparatus to said evaporator, and a suction tube for conduct ng the relatively cold vaporized refrigerant from the evaporator to the refrigerant-compressing apparatus, said capillary and suction tubes being in intimate metallic heat conducting relationship with one another for a substantial portion of their respective lengths, so that the relatively cold suction gas is heated and the relatively warm refrigerant liquid is cooled before it enters the evaporator.

16. In refrigerating apparatus, the combination of a heat insulated cabinet, a refrigerant evaporator for abstracting heat from said cabinet, refrigerant compressing and cooling apparatus outside of said cabinet, a capillary tube for conducting the relatively warm refrigerant from said apparatus to the refrigerant evaporator and providing substantially the sole flow retardation on said refrigerant between said apparatus and said evaporator, a suction conduit for conveying the vaporized refrigerant from said evaporator to said apparatus, a substantial portion of said capillary tube being bonded in intimate metallic heat exchange relationship with a portion of said suction conduit to raise the temperature of said portion of said suction tube above the dew-point temperature of the ambient atmosphere of said portion of the suction conduit, and a second por-- tion of said capillary tube between said bonded portion and said evaporator, said second portion being substantially out of heat exchange relationship with said suction conduit. 1

17. In refrigerating apparatus, the combination of a cabinet embodying a storage compartment and a machinery compartment, an evaporator associated with the storage compartment for abstracting heat therefrom, a compressor and an air-cooled condenser disposed in the machinery compartment, a capillary tube for conveying liquefied refrigerant from said condenser to said evaporator and a suction conduit for conveying vaporized refrigerant from said evaporator to said compressor, both said suction conduit and said capillary tube being bonded by a high heat transmitting material into intimate heat exchange relationship with each other for a substantial distance.

18. In refrigeration apparatus, the combination of a heat insulated cabinet, an evaporator for abstracting heat from said cabinet, refrigerant-supplying apparatus outside of said cabinet, a capillary flow-restricting tube for regulating the flow of warm liquid refrigerant from the refrigerant-supplying apparatus to said evaporator, and a suction tube for conducting the relatively cold vaporized refrigerant from the evaporator to the refrigerant-supplying apparatus, said suction tube being in intimate heat conducting relationship with said capillary tube, and a substantial portion of the both suction and capillary tubes in said intimate heat conducting relationship being convoluted.

GRAHAM S. McCLOY. 

